Microservices maturity model - Practice Problems & Coding Challenges

Challenge - 5 Problems

🧠 Conceptual

intermediate

Understanding the Basic Level of Microservices Maturity

At the initial level of the microservices maturity model, what is the primary characteristic of the services?

A Services are tightly coupled and often deployed together as a monolith.

B Services are loosely coupled and independently deployable with automated testing.

C Services communicate asynchronously using event-driven architecture.

D Services have full observability with distributed tracing and monitoring.

💡 Hint

Think about the starting point before microservices are fully adopted.

The initial level often represents a monolithic or tightly coupled architecture where services are not independently deployable.

❓ Architecture

intermediate

Identifying Characteristics of a Mature Microservices Architecture

Which of the following best describes a mature microservices architecture in terms of service communication and deployment?

A Services communicate synchronously via REST APIs and are deployed together in a single container.

B Services are independently deployable, communicate asynchronously using messaging, and have automated CI/CD pipelines.

C Services share a common database and are deployed as a single unit.

D Services rely on manual deployment and use direct database calls for communication.

💡 Hint

Consider how mature microservices handle deployment and communication for scalability and resilience.

Mature microservices are independently deployable, use asynchronous communication to reduce coupling, and have automated deployment pipelines.

❓ scaling

advanced

Scaling Challenges in Microservices Maturity

At an advanced maturity level, what is a common challenge when scaling microservices, and how is it typically addressed?

A Scaling is limited by a shared database; it is addressed by sharding the database per service.

B Scaling is limited by lack of monitoring; it is addressed by removing logging to improve performance.

C Scaling is limited by manual deployments; it is addressed by reducing the number of services.

D Scaling is limited by synchronous calls; it is addressed by introducing asynchronous messaging and event-driven patterns.

💡 Hint

Think about communication patterns that affect scalability.

Synchronous calls create bottlenecks; asynchronous messaging helps services scale independently and improves resilience.

❓ tradeoff

advanced

Tradeoffs in Microservices Observability at High Maturity

What is a key tradeoff when implementing full observability (distributed tracing, logging, monitoring) in a highly mature microservices system?

A Full observability improves debugging but adds overhead and can impact system performance.

B Improved observability reduces system complexity but increases deployment time.

C Observability eliminates the need for automated testing, reducing development effort.

D Implementing observability removes the need for service-level agreements (SLAs).

💡 Hint

Consider the cost of collecting and processing detailed telemetry data.

While observability helps detect and diagnose issues, it introduces resource overhead that can affect performance.

❓ estimation

expert

Estimating Service Count for Microservices Maturity Transition

A company currently has a monolithic application with 100,000 lines of code. They plan to transition to microservices by splitting the monolith into services averaging 5,000 lines of code each. Approximately how many microservices will they have after the transition?

A 50 microservices

B 200 microservices

C 20 microservices

D 500 microservices

💡 Hint

Divide the total lines of code by the average size per service.

100,000 lines / 5,000 lines per service = 20 services.

Practice

1. What is the primary focus of the first level in the Microservices maturity model?

easy

A. Implementing service discovery

B. Adding automated deployment pipelines

C. Breaking a monolith into independent services

D. Ensuring fault tolerance and resilience

Solution

1. Step 1: Understand the initial maturity level goal

   The first level focuses on decomposing a large monolithic application into smaller, independent microservices.

2. Step 2: Identify what is NOT part of the first level

   Service discovery, automation, and resilience come in later levels, not the first.

3. Final Answer:

   Breaking a monolith into independent services -> Option C

4. Quick Check:

   Level 1 = Decomposition [OK]

Hint: First level means splitting monolith, not automation or resilience [OK]

Common Mistakes:

• Confusing service discovery as first step
• Thinking automation is in the first level
• Assuming resilience is the initial focus

2. Which of the following is the correct syntax to describe the second level in the Microservices maturity model?

easy

A. Services register and discover each other dynamically

B. Services are deployed manually without automation

C. Services communicate synchronously without discovery

D. Services handle failures with retries and circuit breakers

Solution

1. Step 1: Recall the second level feature

   The second level introduces dynamic service registration and discovery to enable services to find each other.

2. Step 2: Eliminate incorrect options

   Synchronous communication without discovery is level 1; manual deployment is level 2 or earlier; failure handling is a later level.

3. Final Answer:

   Services register and discover each other dynamically -> Option A

4. Quick Check:

   Level 2 = Service discovery [OK]

Hint: Level 2 means dynamic discovery, not manual or failure handling [OK]

Common Mistakes:

• Mixing synchronous communication with discovery
• Confusing automation with discovery
• Assuming failure handling is level 2

3. Given a microservices system at maturity level 3, which of the following behaviors would you expect when a service fails?

medium

A. The service automatically retries and uses circuit breakers

B. The system crashes because there is no failure handling

C. Services communicate only via direct IP addresses

D. Deployment is done manually without pipelines

Solution

1. Step 1: Identify level 3 features

   Level 3 focuses on resilience, including retries and circuit breakers to handle failures gracefully.

2. Step 2: Check other options for mismatch

   System crashing means no resilience (level 1 or 2); direct IP communication is basic; manual deployment is unrelated to failure handling.

3. Final Answer:

   The service automatically retries and uses circuit breakers -> Option A

4. Quick Check:

   Level 3 = Resilience with retries [OK]

Hint: Level 3 means automatic failure handling, not crashes or manual steps [OK]

Common Mistakes:

• Assuming no failure handling at level 3
• Confusing communication methods with failure handling
• Ignoring automation in deployment

4. A team claims their microservices system is at maturity level 4 but they still deploy services manually and have no automated rollback. What is the main issue here?

medium

A. They have no failure handling or retries

B. They are missing automation and continuous delivery features

C. They do not have independent services

D. They lack service discovery mechanisms

Solution

1. Step 1: Understand level 4 requirements

   Level 4 focuses on automation, continuous integration, and continuous delivery including automated rollback.

2. Step 2: Identify missing features in the claim

   Manual deployment and no rollback means automation is missing, which contradicts level 4 maturity.

3. Final Answer:

   They are missing automation and continuous delivery features -> Option B

4. Quick Check:

   Level 4 = Automation & CI/CD [OK]

Hint: Level 4 requires automation; manual deploy means not level 4 [OK]

Common Mistakes:

• Confusing service discovery with automation
• Thinking independent services imply automation
• Ignoring rollback as part of automation

5. A company wants to improve their microservices maturity from level 2 to level 4. Which combination of changes should they prioritize?

hard

A. Focus on database scaling and ignore service communication

B. Break monolith into services, add manual deployment, and use direct IP communication

C. Implement retries and circuit breakers only, without automation or discovery

D. Add dynamic service discovery, implement automated deployment pipelines, and introduce failure handling

Solution

1. Step 1: Identify level 2 and level 4 features

   Level 2 includes dynamic service discovery; level 3 introduces failure handling; level 4 adds automation like deployment pipelines.

2. Step 2: Match changes to maturity levels

   Add dynamic service discovery, implement automated deployment pipelines, and introduce failure handling includes discovery (level 2), failure handling (level 3), and automation (level 4), covering needed improvements.

3. Step 3: Eliminate incorrect options

   Break monolith into services, add manual deployment, and use direct IP communication lacks automation and discovery; Implement retries and circuit breakers only, without automation or discovery misses automation; Focus on database scaling and ignore service communication ignores communication and automation.

4. Final Answer:

   Add dynamic service discovery, implement automated deployment pipelines, and introduce failure handling -> Option D

5. Quick Check:

   Level 2 to 4 = Discovery + Automation + Resilience [OK]

Hint: Level 4 needs automation plus discovery and failure handling [OK]

Common Mistakes:

• Ignoring automation when moving to level 4
• Thinking only retries are enough
• Focusing on unrelated scaling aspects